PROJECT SUMMARY The failure of a drug during the development process is extraordinarily costly and dangerous. Indeed, it can take upwards of 10 years and $2-3 billion to develop just one drug, and much of that cost is incurred from the candidates that fail. Most failures occur towards the end of the development process when the costs are highest and when the drug is exposed to the most patients. One of the most common reasons for failure is a compound?s propensity for causing cardiac arrhythmias in patients. In some rare cases, these cardiotoxic effects aren?t even detected during clinical trials and are only discovered once the drug is exposed to the population at large, resulting in harm to patients and a costly withdrawal from the market place. Consequently, the FDA has mandated that all new drugs be tested for cardiotoxic effects, but they and the drug industry realize that current screening tools fall short. This has led to a growing market for screening tools that are more predictive than existing technologies. Human induced pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) represent a promising avenue towards building high-representative in vitro tissue models for preclinical drug screening. However, most hPSC-CM models do not develop into mature, adult-like tissue and thus fail to recapitulate some in vivo drug responses. NanoSurface Biomedical is applying for Phase 1 SBIR funding to develop a combinatorial approach to enhance the maturation of cardiac stem cells for improved drug-induced cardiotoxicity screening based on a simulated microgravity bioreactor-based maturation of stem cells. The approach will generate tissues that are more functionally mature and can be fed into various down-stream assays. We hypothesize that the combination of simulated microgravity, cell patterning, electrical stimulation and metabolic substrates will improve cardiac structural and functional development to enable the collection of cardiotoxicity data with more predictive capacity. To test these hypotheses, this project will focus on the optimization of protocols and cues in combinations that can reproducibly and reliably mature hPSC-CMs. The company will develop protocols and validate the hypothesis that these combinatorial cues can enhance hPSC-CM maturation in vitro. Maturation will be assessed via a suite of structural, electrophysiological, and functional metrics combined with statistical analysis (Aim 1). The most effective maturation protocol will be used to generate hPSC-CM for validation using downstream drug toxicity assays (Aim 2). These data will be used to assess the validity of the approach for eventual scale up during Phase 2 for the development of highly predictive in vitro cardiac assays, and for commercial release and market delivery in Phase 3. Successful validation of the company?s combinatorial approach will produce an innovative new product aimed at relieving critical deficiencies in preclinical toxicity models and reduce cost and time in the drug development process.